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  • ItemPublished versionOpen Access
    Feasibility of incorporating objective measures of physical activity in the STEPS program. A pilot study in Malawi
    (2020-01-31) Westgate, K; Ridgway, C; Rennie, K; Strain, T; Wijndaele, K; Brage, Soren; Westgate, Kate [0000-0002-0283-3562]; Rennie, Kirsten [0000-0003-2690-1934]; Strain, Tessa [0000-0002-7086-1047]; Wijndaele, Katrien [0000-0003-2199-7981]; Brage, Soren [0000-0002-1265-7355]
    Background Physical activity is an important determinant of human health but it is inherently difficult to measure. Global surveillance systems for physical activity have so far only included self-report measures, which capture only a small subset of daily activity and are limited due to issues of recall bias. Wrist-worn accelerometry offers a reasonably cost-effective objective method of measuring physical activity during free-living with proven feasibility in large-scale population studies. The key objective of this project was to pilot wrist-worn accelerometry within a surveillance setting in order to inform the implementation of this methodology into the global WHO STEPS programme. Method development and implementation Accelerometry protocols were developed and deployed within an existing STEPS survey in two regions of Malawi (Dowa and Lilongwe). This also included developing training for local staff. Survey information was collected on tablets. Accelerometers could only be set up on PCs, so the protocol was adapted to do this in advance of recruiting participants. For this, an alternative Participant ID linkage system was developed to enable linking accelerometer files to the rest of the survey data. On the whole, the implementation was successful. During the process evaluation, some issues were identified. For example, black wrist straps were culturally associated with the Devil by some participants. A total of 499 participants were recruited for Step 1 and 2, of whom 446 returned for Step 3 measurements which included accelerometry. The accelerometry data collection was well accepted by both fieldwork team members and study participants, with only four participants (<1% of those eligible) declining to wear the device. There were no major technical issues with devices, although a small number of wrist straps were damaged and 13 monitors were lost (3% of deployed). Of 456 accelerometer files retrieved, 410 files (90%) could be linked to survey participants. All but two accelerometer files could be processed with standard techniques to produce participant-level summary results. Sufficient valid data (defined as at least 48 hours of monitor wear time with reasonable diurnal representation) were available for 386 survey participants (87% of eligible). Results Objective levels of physical activity in Malawi from this pilot study were about 50% higher than levels observed in the UK using similar methodology. Rural dwellers were more active than urban dwellers, particularly in the morning hours of the day. Men had higher activity levels compared to women, and there were decreasing trends with advancing age. Conclusion and recommendations This pilot demonstrated that it is feasible to implement wrist-worn accelerometry within the STEPS program in settings such as Malawi. Detailed description of objectively measured physical activity patterns could be produced from nearly all accelerometer files retrieved, including behavioural indicators known to be important for human health. In future surveys, culturally specific issues that could impact data collection should be identified early in the fieldwork planning stage and changes to the protocol made. Experiences from this pilot have led to development of software platforms that allow accelerometers to be set up from Android tablets at the point of issuing the device to the participant, which would simplify future fieldwork training and reduce risk of data linkage error.
  • ItemAccepted versionOpen Access
    What works to promote walking at the population level? A systematic review.
    (BMJ, 2018-06) Foster, Charlie; Kelly, Paul; Reid, Hamish AB; Roberts, Nia; Murtagh, Elaine M; Humphreys, David K; Panter, Jenna; Milton, Karen; Panter, Jenna [0000-0001-8870-718X]
    OBJECTIVE: Interventions to promote walking have focused on individual or group-based approaches, often via the randomised controlled trial design. Walking can also be promoted using population health approaches. We systematically reviewed the effectiveness of population approaches to promote walking among individuals and populations. DESIGN: A systematic review. DATA SOURCES: 10 electronic databases searched from January 1990 to March 2017. ELIGIBILITY CRITERIA: Eligibility criteria include pre-experimental and postexperimental studies of the effects of population interventions to change walking, and the effects must have been compared with a 'no intervention', or comparison group/area/population, or variation in exposure; duration of ≥12 months of follow up; participants in free-living populations; and English-language articles. RESULTS: 12 studies were identified from mostly urban high-income countries (one focusing on using tax, incentivising the loss of parking spaces; and one using policy only, permitting off-leash dogs in city parks). Five studies used mass media with either environment (n=2) or community (n=3) approaches. Four studies used environmental changes that were combined with policies. One study had scaled up school-based approaches to promote safe routes to schools. We found mass media, community initiatives and environmental change approaches increased walking (range from 9 to 75 min/week).
  • ItemPublished versionOpen Access
    Physical activity patterns across time-segmented youth sport flag football practice.
    (Springer nature, 2018-02-08) Schlechter, Chelsey R; Guagliano, Justin M; Rosenkranz, Richard R; Milliken, George A; Dzewaltowski, David A; Guagliano, Justin [0000-0002-4450-5700]
    BACKGROUND: Youth sport (YS) reaches a large number of children world-wide and contributes substantially to children's daily physical activity (PA), yet less than half of YS time has been shown to be spent in moderate-to-vigorous physical activity (MVPA). Physical activity during practice is likely to vary depending on practice structure that changes across YS time, therefore the purpose of this study was 1) to describe the type and frequency of segments of time, defined by contextual characteristics of practice structure, during YS practices and 2) determine the influence of these segments on PA. METHODS: Research assistants video-recorded the full duration of 28 practices from 14 boys' flag football teams (2 practices/team) while children concurrently (N = 111, aged 5-11 years, mean 7.9 ± 1.2 years) wore ActiGraph GT1M accelerometers to measure PA. Observers divided videos of each practice into continuous context time segments (N = 204; mean-segments-per-practice = 7.3, SD = 2.5) using start/stop points defined by change in context characteristics, and assigned a value for task (e.g., management, gameplay, etc.), member arrangement (e.g., small group, whole group, etc.), and setting demand (i.e., fosters participation, fosters exclusion). Segments were then paired with accelerometer data. Data were analyzed using a multilevel model with segment as unit of analysis. RESULTS: Whole practices averaged 34 ± 2.4% of time spent in MVPA. Free-play (51.5 ± 5.5%), gameplay (53.6 ± 3.7%), and warm-up (53.9 ± 3.6%) segments had greater percentage of time (%time) in MVPA compared to fitness (36.8 ± 4.4%) segments (p ≤ .01). Greater %time was spent in MVPA during free-play segments compared to scrimmage (30.2 ± 4.6%), strategy (30.6 ± 3.2%), and sport-skill (31.6 ± 3.1%) segments (p ≤ .01), and in segments that fostered participation (36.1 ± 2.7%) than segments that fostered exclusion (29.1 ± 3.0%; p ≤ .01). Significantly greater %time was spent in low-energy stationary behavior in fitness (15.7 ± 3.4%) than gameplay (4.0 ± 2.9%) segments (p ≤ .01), and in sport-skill (17.6 ± 2.2%) than free-play (8.2 ± 4.2%), gameplay, and warm-up (10.6 ± 2.6%) segments (p < .05). CONCLUSIONS: The %time spent in low-energy stationary behavior and in MVPA differed by characteristics of task and setting demand of the segment. Restructuring the routine of YS practice to include segments conducive to MVPA could increase %time spent in MVPA during practice. As YS reaches a large number of children worldwide, increasing PA during YS has the potential to create a public health impact.
  • ItemAccepted versionOpen Access
    Socioeconomic position and sedentary behavior in Brazilian adolescents: A life-course approach.
    (Elsevier, 2018-02) Mielke, Gregore I; Brown, Wendy J; Ekelund, Ulf; Brage, Soren; Gonçalves, Helen; Wehrmeister, Fernando C; Menezes, Ana M; Hallal, Pedro C; Brage, Soren [0000-0002-1265-7355]
    Socioeconomic position (SEP) is a potential correlate of sedentary behavior in adolescents. The aim of this study was to examine the associations between SEP and self-reported and objective measures of sedentary behavior in adolescents, using a life-course approach. Data from the 1993 Pelotas (Brazil) Birth Cohort Study were analyzed (N=5249). Cross-sectional and longitudinal associations between multiple SEP indicators (maternal education, family income, SEP composite, cumulative family income) at birth, 11, 15 and 18years, and five sedentary behavior outcomes (≥4h/day screen time; ≥4h/day TV; ≥2h/day computer; ≥2h/day video game; ≥12.7h/day objectively measured sedentary time) at 11, 15 and 18years, were examined. In cross-sectional analyses, higher SEP was positively associated with more screen time at ages 11 and 15years. There was a consistent and positive association between higher SEP with time spent using a computer, and with sedentary time assessed through accelerometry. SEP at birth had a positive and direct effect on screen, computer and total sedentary time at 18years. Participants in the highest cumulative income group had higher odds of high sedentary behavior in screen (OR: 2.40; 95% CI: 1.50-3.54), computer (OR: 7.35; 95% CI: 4.19-12.89) and total sedentary time (OR: 5.40; 95% CI: 3.53-10.35), respectively, compared with their counterparts with lower cumulative income. Our findings showed that SEP is an early determinant of sedentary behavior in adolescents.
  • ItemAccepted versionOpen Access
    Associations of lifestyle factors with serum dehydroepiandrosterone sulphate and insulin-like growth factor-1 concentration in prepubertal children.
    (Wiley, 2018-01-15) Mäntyselkä, Aino; Jääskeläinen, Jarmo; Eloranta, Aino-Maija; Väistö, Juuso; Voutilainen, Raimo; Ong, Ken; Brage, Søren; Lakka, Timo A; Lindi, Virpi; Ong, Kenneth [0000-0003-4689-7530]; Brage, Soren [0000-0002-1265-7355]
    OBJECTIVE: Little is known about the relationships of dietary factors, physical activity and sedentary behaviour to dehydroepiandrosterone sulphate (DHEAS) and insulin-like growth factor-1 (IGF-1) concentrations among prepubertal children. Therefore, we studied the associations of these lifestyle factors with serum DHEAS and IGF-1 in children. DESIGN AND SUBJECTS: Cross-sectional analysis of a population sample of 431 prepubertal children aged 6-9 years. MEASUREMENTS: Assessment of dietary factors by food records and physical activity and sedentary behaviour by a combined heart rate and movement monitor and a questionnaire. Measurement of serum DHEAS and IGF-1. RESULTS: Consumption of low-fibre grain products (standardized regression coefficient β = .118, P = .017) and intake of vegetable protein (β = .100, P = .045) was positively and consumption of sugar-sweetened beverages (β = -.117, P = .018) was inversely associated with DHEAS after adjustment for sex, age and body fat percentage. Energy intake (β = .160, P = .001) was positively associated with IGF-1 adjusting for sex, age and body fat percentage. Vigorous physical activity was inversely associated with DHEAS after adjustment for sex and age (β = -.120, P = .027), and total (β = -.137, P = .007), moderate (β = -.130, P = .012), vigorous (β = -.136, P = .011) and moderate to vigorous physical activity (β = -.160, P = .003) were inversely and total sedentary behaviour (β = .151, P = .003) was positively associated with IGF-1 adjusting for sex and age. None of physical activity measures was associated with DHEAS or IGF-1 after additional adjustment for body fat percentage. CONCLUSIONS: Lifestyle factors have weak and moderate associations with biochemical markers of adrenarche in prepubertal children. These associations indicate body fat independent and dependent influences of diet and physical activity, respectively.
  • ItemPublished versionOpen Access
    Prioritising Risk Factors for Type 2 Diabetes: Causal Inference through Genetic Approaches.
    (Springer Science and Business Media LLC, 2018-05-19) Wittemans, Laura BL; Lotta, Luca A; Langenberg, Claudia; Wittemans, Laura [0000-0001-6588-938X]; Langenberg, Claudia [0000-0002-5017-7344]
    PURPOSE OF THE REVIEW: Causality has been demonstrated for few of the many putative risk factors for type 2 diabetes (T2D) emerging from observational epidemiology. Genetic approaches are increasingly being used to infer causality, and in this review, we discuss how genetic discoveries have shaped our understanding of the causal role of factors associated with T2D. RECENT FINDINGS: Genetic discoveries have led to the identification of novel potential aetiological factors of T2D, including the protective role of peripheral fat storage capacity and specific metabolic pathways, such as the branched-chain amino acid breakdown. Consideration of specific genetic mechanisms contributing to overall lipid levels has suggested that distinct physiological processes influencing lipid levels may influence diabetes risk differentially. Genetic approaches have also been used to investigate the role of T2D and related metabolic traits as causal risk factors for other disease outcomes, such as cancer, but comprehensive studies are lacking. Genome-wide association studies of T2D and metabolic traits coupled with high-throughput molecular phenotyping and in-depth characterisation and follow-up of individual loci have provided better understanding of aetiological factors contributing to T2D.
  • ItemPublished versionOpen Access
    Elucidating the genetic architecture of reproductive ageing in the Japanese population.
    (Springer Science and Business Media LLC, 2018-05-17) Horikoshi, Momoko; Day, Felix R; Akiyama, Masato; Hirata, Makoto; Kamatani, Yoichiro; Matsuda, Koichi; Ishigaki, Kazuyoshi; Kanai, Masahiro; Wright, Hollis; Toro, Carlos A; Ojeda, Sergio R; Lomniczi, Alejandro; Kubo, Michiaki; Ong, Ken K; Perry, John RB; Day, Felix R [0000-0003-3789-7651]; Kamatani, Yoichiro [0000-0001-8748-5597]; Matsuda, Koichi [0000-0001-7292-2686]; Toro, Carlos A [0000-0002-7355-7534]; Lomniczi, Alejandro [0000-0003-4535-0103]
    Population studies elucidating the genetic architecture of reproductive ageing have been largely limited to European ancestries, restricting the generalizability of the findings and overlooking possible key genes poorly captured by common European genetic variation. Here, we report 26 loci (all P < 5 × 10-8) for reproductive ageing, i.e. puberty timing or age at menopause, in a non-European population (up to 67,029 women of Japanese ancestry). Highlighted genes for menopause include GNRH1, which supports a primary, rather than passive, role for hypothalamic-pituitary GnRH signalling in the timing of menopause. For puberty timing, we demonstrate an aetiological role for receptor-like protein tyrosine phosphatases by combining evidence across population genetics and pre- and peri-pubertal changes in hypothalamic gene expression in rodent and primate models. Furthermore, our findings demonstrate widespread differences in allele frequencies and effect estimates between Japanese and European associated variants, highlighting the benefits and challenges of large-scale trans-ethnic approaches.
  • ItemPublished versionOpen Access
    Daylight saving time as a potential public health intervention: an observational study of evening daylight and objectively-measured physical activity among 23,000 children from 9 countries.
    (Springer Science and Business Media LLC, 2014-10-23) Goodman, Anna; Page, Angie S; Cooper, Ashley R; International Children’s Accelerometry Database (ICAD) Collaborators
    BACKGROUND: It has been proposed that introducing daylight saving measures could increase children's physical activity, but there exists little research on this issue. This study therefore examined associations between time of sunset and activity levels, including using the bi-annual 'changing of the clocks' as a natural experiment. METHODS: 23,188 children aged 5-16 years from 15 studies in nine countries were brought together in the International Children's Accelerometry Database. 439 of these children were of particular interest for our analyses as they contributed data both immediately before and after the clocks changed. All children provided objectively-measured physical activity data from Actigraph accelerometers, and we used their average physical activity level (accelerometer counts per minute) as our primary outcome. Date of accelerometer data collection was matched to time of sunset, and to weather characteristics including daily precipitation, humidity, wind speed and temperature. RESULTS: Adjusting for child and weather covariates, we found that longer evening daylight was independently associated with a small increase in daily physical activity. Consistent with a causal interpretation, the magnitude of these associations was largest in the late afternoon and early evening and these associations were also evident when comparing the same child just before and just after the clocks changed. These associations were, however, only consistently observed in the five mainland European, four English and two Australian samples (adjusted, pooled effect sizes 0.03-0.07 standard deviations per hour of additional evening daylight). In some settings there was some evidence of larger associations between daylength and physical activity in boys. There was no evidence of interactions with weight status or maternal education, and inconsistent findings for interactions with age. CONCLUSIONS: In Europe and Australia, evening daylight seems to play a causal role in increasing children's activity in a relatively equitable manner. Although the average increase in activity is small in absolute terms, these increases apply across all children in a population. Moreover, these small effect sizes actually compare relatively favourably with the typical effect of intensive, individual-level interventions. We therefore conclude that, by shifting the physical activity mean of the entire population, the introduction of additional daylight saving measures could yield worthwhile public health benefits.
  • ItemPublished versionOpen Access
    Taking account of context in population health intervention research: guidance for producers, users and funders of research
    (National Institute for Health and Care Research) Craig, Peter; Di Ruggiero, Erica; Frohlich, Katherine L; Mykhalovskiy, Eric; White, Martin; Campbell, Rona; Cummins, Steven; Edwards, Nancy; Hunt, Kate; Kee, Frank; Loppie, Charlotte; Moore, Laurence; Ogilvie, David; Petticrew, Mark; Poland, Blake; Ridde, Valéry; Shoveller, Jeannie; Viehbeck, Sarah; Wight, Daniel; Craig, Peter [0000-0002-7653-5832]; Di Ruggiero, Erica [0000-0002-8935-7908]; Frohlich, Katherine L [0000-0002-5519-2455]; Mykhalovskiy, Eric [0000-0002-7518-7784]; White, Martin [0000-0002-1861-6757]; Campbell, Rona [0000-0002-1099-9319]; Cummins, Steven [0000-0002-3957-4357]; Edwards, Nancy [0000-0002-3117-5888]; Hunt, Kate [0000-0002-5873-3632]; Kee, Frank [0000-0002-0606-8167]; Loppie, Charlotte [0000-0002-1038-1236]; Moore, Laurence [0000-0003-2182-823X]; Ogilvie, David [0000-0002-0270-4672]; Petticrew, Mark [0000-0002-6378-5517]; Poland, Blake [0000-0002-3774-9758]; Ridde, Valéry [0000-0001-9299-8266]; Shoveller, Jeannie [0000-0002-4616-3556]; Viehbeck, Sarah [0000-0002-3110-1432]; Wight, Daniel [0000-0002-1234-3110]
    Population health intervention research (PHIR) seeks to develop and evaluate policies, programmes and other types of interventions that may affect population health and health equity. Such interventions are strongly influenced by context – taken to refer to any feature of the circumstances in which an intervention is conceived, developed, implemented and evaluated. Understanding how interventions relate to context is critical to understanding how they work; why they sometimes fail; whether they can be successfully adapted, scaled up or translated from one context to another; why their impacts vary; and how far effects observed in one context can be generalised to others. Concerns that context has been neglected in research to develop and evaluate population health interventions have been expressed for at least 20 years. Over this period, an increasingly comprehensive body of guidance has been developed to help with the design, conduct, reporting and appraisal of PHIR. References to context have become more frequent in recent years, as interest has grown in complex and upstream interventions, systems thinking and realist approaches to evaluation, but there remains a lack of systematic guidance for producers, users and funders of PHIR on how context should be taken into account. This document draws together recent thinking and practical experience of addressing context within PHIR. It provides a broad, working definition of context and explains why and how context is important to PHIR. It identifies the dimensions of context that are likely to shape how interventions are conceptualised, the impacts that they have and how they can be implemented, translated and scaled up. It suggests how context should be taken into account throughout the PHIR process, from priority setting and intervention development to the design and conduct of evaluations and reporting, synthesis and knowledge exchange. It concludes by summarising the key messages for producers, users and funders of PHIR and suggesting priorities for future research. The document is meant to be used alongside existing guidance for the development, evaluation and reporting of population health interventions. We expect the guidance to evolve over time, as practice changes in the light of the guidance and experience accumulates on useful approaches. The work was funded by the Canadian Institutes of Health Research ( – Institute of Population and Public Health (CIHR-IPPH) and the UK National Institute for Health Research (NIHR).
  • ItemPublished versionOpen Access
    Do Natural Experiments of Changes in Neighborhood Built Environment Impact Physical Activity and Diet? A Systematic Review.
    (MDPI AG, 2018-01-26) MacMillan, Freya; George, Emma S; Feng, Xiaoqi; Merom, Dafna; Bennie, Andrew; Cook, Amelia; Sanders, Taren; Dwyer, Genevieve; Pang, Bonnie; Guagliano, Justin M; Kolt, Gregory S; Astell-Burt, Thomas; MacMillan, Freya [0000-0003-3176-2465]; Pang, Bonnie [0000-0002-4450-5700]; Guagliano, Justin M [0000-0002-9223-3324]; Astell-Burt, Thomas [0000-0002-4504-6008]
    Physical activity and diet are major modifiable risk factors for chronic disease and have been shown to be associated with neighborhood built environment. Systematic review evidence from longitudinal studies on the impact of changing the built environment on physical activity and diet is currently lacking. A systematic review of natural experiments of neighborhood built environment was conducted. The aims of this systematic review were to summarize study characteristics, study quality, and impact of changes in neighborhood built environment on physical activity and diet outcomes among residents. Natural experiments of neighborhood built environment change, exploring longitudinal impacts on physical activity and/or diet in residents, were included. From five electronic databases, 2084 references were identified. A narrative synthesis was conducted, considering results in relation to study quality. Nineteen papers, reporting on 15 different exposures met inclusion criteria. Four studies included a comparison group and 11 were pre-post/longitudinal studies without a comparison group. Studies reported on the impact of redeveloping or introducing cycle and/or walking trails (n = 5), rail stops/lines (n = 4), supermarkets and farmers' markets (n = 4) and park and green space (n = 2). Eight/15 studies reported at least one beneficial change in physical activity, diet or another associated health outcome. Due to limitations in study design and reporting, as well as the wide array of outcome measures reported, drawing conclusions to inform policy was challenging. Future research should consider a consistent approach to measure the same outcomes (e.g., using measurement methods that collect comparable physical activity and diet outcome data), to allow for pooled analyses. Additionally, including comparison groups wherever possible and ensuring high quality reporting is essential.
  • ItemPublished versionOpen Access
    Cycling in Warsaw, Poland - Perceived enablers and barriers according to cyclists and non-cyclists.
    (Elsevier BV, 2018-07) Iwińska, Katarzyna; Blicharska, Malgorzata; Pierotti, Livia; Tainio, Marko; de Nazelle, Audrey; Tainio, Marko [0000-0002-0973-2342]
    Cycling in urban environments provides many benefits to people. However, planning of cycling infrastructures in large cities faces numerous challenges and requires better understanding of both the factors enabling cycling as well as barriers to it, determined by particular local context. While there is a growing body of research that tackle the bike transport related questions in Western Europe and the USA, there is relatively little research on that in Central Eastern Europe (CEE), in post-communist countries. In this study we used qualitative and quantitative methods to explore urban cyclists and non-cyclists opinions about the cycling, the perceived problems and obstacles, and perception of the on-going changes in bicycle transportation system in Warsaw, Poland. Although many people see potential advantages of cycling, it is mostly perceived as a leisure time activity. Those who do utilitarian cycling are more acutely aware of the benefits, such as rapidity and flexibility of this mean of transport. The main perceived barriers are linked to lack of good cycling infrastructure in the city, the feeling of insecurity linked to the behaviour of drivers, and to maintenance during winter. In conclusion, our research highlights both the opportunities and challenges linked to the development of improved cycle transportation system, suggesting the need for a range of policies, from the infrastructure improvements and comprehensive planning of the whole transportation system, to improving the driving culture that would support feeling of security of the cyclists.
  • ItemPublished versionOpen Access
    The international medical community must act to help Rohingya refugees in Bangladesh
    (BMJ, 2018-03-12) Islam, Nazrul; Islam, Nazrul [0000-0003-3982-4325]
    The forced displacement of the Rohingya population has a historical root since the late 1970s. Approximately 200,000 Rohingya were displaced to neighbouring Bangladesh in 1978, and about 260,000 in 1991-92. [1] The recent displacement of 400,000-420,000 Rohingya, of which about 240,000 were children, made it by far the largest displacement of Rohingya population. [2] The total Rohingya population living in Myanmar-bordered-Cox’s Bazar peninsula has been estimated to be about 950,000. [3]
  • ItemPublished versionOpen Access
    Cross-Sectional Associations of Reallocating Time Between Sedentary and Active Behaviours on Cardiometabolic Risk Factors in Young People: An International Children's Accelerometry Database (ICAD) Analysis.
    (Springer Science and Business Media LLC, 2018-10) Hansen, Bjørge Herman; Anderssen, Sigmund Alfred; Andersen, Lars Bo; Hildebrand, Maria; Kolle, Elin; Steene-Johannessen, Jostein; Kriemler, Susi; Page, Angie S; Puder, Jardena J; Reilly, John J; Sardinha, Luis B; van Sluijs, Esther MF; Wedderkopp, Niels; Ekelund, Ulf; International Children’s Accelerometry Database (ICAD) Collaborators; Van Sluijs, Esther [0000-0001-9141-9082]
    INTRODUCTION: Sedentary time and time spent in various intensity-specific physical activity are co-dependent, and increasing time spent in one behaviour requires decreased time in another. OBJECTIVE: The aim of the present study was to examine the theoretical associations with reallocating time between categories of intensities and cardiometabolic risk factors in a large and heterogeneous sample of children and adolescents. METHODS: We analysed pooled data from 13 studies comprising 18,200 children and adolescents aged 4-18 years from the International Children's Accelerometry Database (ICAD). Waist-mounted accelerometers measured sedentary time, light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA). Cardiometabolic risk factors included waist circumference (WC), systolic blood pressure (SBP), fasting high- and low-density lipoprotein cholesterol (HDL-C and LDL-C), triglycerides, insulin, and glucose. Associations of reallocating time between the various intensity categories with cardiometabolic risk factors were explored using isotemporal substitution modelling. RESULTS: Replacing 10 min of sedentary time with 10 min of MVPA showed favourable associations with WC, SBP, LDL-C, insulin, triglycerides, and glucose; the greatest magnitude was observed for insulin (reduction of 2-4%), WC (reduction of 0.5-1%), and triglycerides (1-2%). In addition, replacing 10 min of sedentary time with an equal amount of LPA showed beneficial associations with WC, although only in adolescents. CONCLUSIONS: Replacing sedentary time and/or LPA with MVPA in children and adolescents is favourably associated with most markers of cardiometabolic risk. Efforts aimed at replacing sedentary time with active behaviours, particularly those of at least moderate intensity, appear to be an effective strategy to reduce cardiometabolic risk in young people.
  • ItemPublished versionOpen Access
    Identifying and correcting epigenetics measurements for systematic sources of variation.
    (Springer Science and Business Media LLC, 2018) Perrier, Flavie; Novoloaca, Alexei; Ambatipudi, Srikant; Baglietto, Laura; Ghantous, Akram; Perduca, Vittorio; Barrdahl, Myrto; Harlid, Sophia; Ong, Ken K; Cardona, Alexia; Polidoro, Silvia; Nøst, Therese Haugdahl; Overvad, Kim; Omichessan, Hanane; Dollé, Martijn; Bamia, Christina; Huerta, José Marìa; Vineis, Paolo; Herceg, Zdenko; Romieu, Isabelle; Ferrari, Pietro; Ong, Kenneth [0000-0003-4689-7530]; Cardona, Alexia [0000-0002-7877-5565]
    BACKGROUND: Methylation measures quantified by microarray techniques can be affected by systematic variation due to the technical processing of samples, which may compromise the accuracy of the measurement process and contribute to bias the estimate of the association under investigation. The quantification of the contribution of the systematic source of variation is challenging in datasets characterized by hundreds of thousands of features.In this study, we introduce a method previously developed for the analysis of metabolomics data to evaluate the performance of existing normalizing techniques to correct for unwanted variation. Illumina Infinium HumanMethylation450K was used to acquire methylation levels in over 421,000 CpG sites for 902 study participants of a case-control study on breast cancer nested within the EPIC cohort. The principal component partial R-square (PC-PR2) analysis was used to identify and quantify the variability attributable to potential systematic sources of variation. Three correcting techniques, namely ComBat, surrogate variables analysis (SVA) and a linear regression model to compute residuals were applied. The impact of each correcting method on the association between smoking status and DNA methylation levels was evaluated, and results were compared with findings from a large meta-analysis. RESULTS: A sizeable proportion of systematic variability due to variables expressing 'batch' and 'sample position' within 'chip' was identified, with values of the partial R2 statistics equal to 9.5 and 11.4% of total variation, respectively. After application of ComBat or the residuals' methods, the contribution was 1.3 and 0.2%, respectively. The SVA technique resulted in a reduced variability due to 'batch' (1.3%) and 'sample position' (0.6%), and in a diminished variability attributable to 'chip' within a batch (0.9%). After ComBat or the residuals' corrections, a larger number of significant sites (k = 600 and k = 427, respectively) were associated to smoking status than the SVA correction (k = 96). CONCLUSIONS: The three correction methods removed systematic variation in DNA methylation data, as assessed by the PC-PR2, which lent itself as a useful tool to explore variability in large dimension data. SVA produced more conservative findings than ComBat in the association between smoking and DNA methylation.
  • ItemPublished versionOpen Access
    Longitudinal association between change in the neighbourhood built environment and the wellbeing of local residents in deprived areas: an observational study.
    (Springer Science and Business Media LLC, 2018-04-24) Foley, Louise; Coombes, Emma; Hayman, Dan; Humphreys, David; Jones, Andrew; Mitchell, Richard; Ogilvie, David; Foley, Louise [0000-0003-3028-7340]
    BACKGROUND: Features of the urban neighbourhood influence the physical, social and mental wellbeing of residents and communities. We explored the longitudinal association between change to the neighbourhood built environment and the wellbeing of local residents in deprived areas of Glasgow, Scotland. METHODS: A cohort of residents (n = 365; mean age 50 years; 44% male; 4.1% of the 9000 mailed surveys at baseline) responded to a postal survey in 2005 and 2013. Wellbeing was assessed with the mental (MCS-8) and physical (PCS-8) components of the SF-8 scale. We developed software to aid identification of visible changes in satellite imagery occurring over time. We then used a Geographical Information System to calculate the percentage change in the built environment occurring within an 800 m buffer of each participant's home. RESULTS: The median change in the neighbourhood built environment was 3% (interquartile range 6%). In the whole sample, physical wellbeing declined by 1.5 units on average, and mental wellbeing increased by 0.9 units, over time. In multivariable linear regression analyses, participants living in neighbourhoods with a greater amount of change in the built environment (unit change = 1%) experienced significantly reduced physical (PCS-8: -0.13, 95% CI -0.26 to 0.00) and mental (MCS-8: -0.16, 95% CI -0.31 to - 0.02) wellbeing over time compared to those living in neighbourhoods with less change. For mental wellbeing, a significant interaction by baseline perception of financial strain indicated a larger reduction in those experiencing greater financial strain (MCS-8: -0.22, 95% CI -0.39 to - 0.06). However, this relationship was reversed in those experiencing lower financial strain, whereby living in neighbourhoods with a greater amount of change was associated with significantly improved mental wellbeing over time (MCS-8: 0.38, 95% CI 0.04 to 0.72). CONCLUSIONS: Overall, we found some evidence that living in neighbourhoods experiencing higher levels of physical change worsened wellbeing in local residents. However, we found a stronger negative relationship in those with lower financial security and a positive relationship in those with higher financial security. This is one of few studies exploring the longitudinal relationship between the environment and health.
  • ItemPublished versionOpen Access
    Prospective association between handgrip strength and cardiac structure and function in UK adults.
    (Public Library of Science (PLoS), 2018) Beyer, Sebastian E; Sanghvi, Mihir M; Aung, Nay; Hosking, Alice; Cooper, Jackie A; Paiva, José Miguel; Lee, Aaron M; Fung, Kenneth; Lukaschuk, Elena; Carapella, Valentina; Mittleman, Murray A; Brage, Soren; Piechnik, Stefan K; Neubauer, Stefan; Petersen, Steffen E; Brage, Soren [0000-0002-1265-7355]
    BACKGROUND: Handgrip strength, a measure of muscular fitness, is associated with cardiovascular (CV) events and CV mortality but its association with cardiac structure and function is unknown. The goal of this study was to determine if handgrip strength is associated with changes in cardiac structure and function in UK adults. METHODS AND RESULTS: Left ventricular (LV) ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), mass (M), and mass-to-volume ratio (MVR) were measured in a sample of 4,654 participants of the UK Biobank Study 6.3 ± 1 years after baseline using cardiovascular magnetic resonance (CMR). Handgrip strength was measured at baseline and at the imaging follow-up examination. We determined the association between handgrip strength at baseline as well as its change over time and each of the cardiac outcome parameters. After adjustment, higher level of handgrip strength at baseline was associated with higher LVEDV (difference per SD increase in handgrip strength: 1.3ml, 95% CI 0.1-2.4; p = 0.034), higher LVSV (1.0ml, 0.3-1.8; p = 0.006), lower LVM (-1.0g, -1.8 --0.3; p = 0.007), and lower LVMVR (-0.013g/ml, -0.018 --0.007; p<0.001). The association between handgrip strength and LVEDV and LVSV was strongest among younger individuals, while the association with LVM and LVMVR was strongest among older individuals. CONCLUSIONS: Better handgrip strength was associated with cardiac structure and function in a pattern indicative of less cardiac hypertrophy and remodeling. These characteristics are known to be associated with a lower risk of cardiovascular events.
  • ItemPublished versionOpen Access
    Replication of a Gene-Diet Interaction at CD36, NOS3 and PPARG in Response to Omega-3 Fatty Acid Supplements on Blood Lipids: A Double-Blind Randomized Controlled Trial.
    (Elsevier BV, 2018-05) Zheng, Ju-Sheng; Chen, Jiewen; Wang, Ling; Yang, Hong; Fang, Ling; Yu, Ying; Yuan, Liping; Feng, Jueping; Li, Kelei; Tang, Jun; Lin, Mei; Lai, Chao-Qiang; Li, Duo; Zheng, Jusheng [0000-0001-6560-4890]
    BACKGROUND: Modulation of genetic variants on the effect of omega-3 fatty acid supplements on blood lipids is still unclear. METHODS: In a double-blind randomized controlled trial, 150 patients with type 2 diabetes (T2D) were randomized into omega-3 fatty acid group (n = 56 for fish oil and 44 for flaxseed oil) and control group (n = 50) for 180 days. All patients were genotyped for genetic variants at CD36 (rs1527483), NOS3 (rs1799983) and PPARG (rs1801282). Linear regression was used to examine the interaction between omega-3 fatty acid intervention and CD36, NOS3 or PPARG variants for blood lipids. FINDINGS: Significant interaction with omega-3 fatty acid supplements was observed for CD36 on triglycerides (p-interaction = 0.042) and PPAGR on low-density lipoprotein-cholesterol (p-interaction = 0.02). We also found a significant interaction between change in erythrocyte phospholipid omega-3 fatty acid composition and NOS3 genotype on triglycerides (p-interaction = 0.042), total cholesterol (p-interaction = 0.013) and ratio of total cholesterol to high-density lipoprotein cholesterol (p-interaction = 0.015). The T2D patients of CD36-G allele, PPARG-G allele and NOS3-A allele tended to respond better to omega-3 fatty acids in improving lipid profiles. The interaction results of the omega-3 fatty acid group were mainly attributed to the fish oil supplements. INTERPRETATION: This study suggests that T2D patients with different genotypes at CD36, NOS3 and PPARG respond differentially to intervention of omega-3 supplements in blood lipid profiles.
  • ItemPublished versionOpen Access
    Sedentary Behavior Research Network (SBRN) - Terminology Consensus Project process and outcome.
    (Springer Science and Business Media LLC, 2017-06-10) Tremblay, Mark S; Aubert, Salomé; Barnes, Joel D; Saunders, Travis J; Carson, Valerie; Latimer-Cheung, Amy E; Chastin, Sebastien FM; Altenburg, Teatske M; Chinapaw, Mai JM; SBRN Terminology Consensus Project Participants
    BACKGROUND: The prominence of sedentary behavior research in health science has grown rapidly. With this growth there is increasing urgency for clear, common and accepted terminology and definitions. Such standardization is difficult to achieve, especially across multi-disciplinary researchers, practitioners, and industries. The Sedentary Behavior Research Network (SBRN) undertook a Terminology Consensus Project to address this need. METHOD: First, a literature review was completed to identify key terms in sedentary behavior research. These key terms were then reviewed and modified by a Steering Committee formed by SBRN. Next, SBRN members were invited to contribute to this project and interested participants reviewed and provided feedback on the proposed list of terms and draft definitions through an online survey. Finally, a conceptual model and consensus definitions (including caveats and examples for all age groups and functional abilities) were finalized based on the feedback received from the 87 SBRN member participants who responded to the original invitation and survey. RESULTS: Consensus definitions for the terms physical inactivity, stationary behavior, sedentary behavior, standing, screen time, non-screen-based sedentary time, sitting, reclining, lying, sedentary behavior pattern, as well as how the terms bouts, breaks, and interruptions should be used in this context are provided. CONCLUSION: It is hoped that the definitions resulting from this comprehensive, transparent, and broad-based participatory process will result in standardized terminology that is widely supported and adopted, thereby advancing future research, interventions, policies, and practices related to sedentary behaviors.
  • ItemPublished versionOpen Access
    Estimating city-level travel patterns using street imagery: A case study of using Google Street View in Britain.
    (Public Library of Science (PLoS), 2018) Goel, Rahul; Garcia, Leandro MT; Goodman, Anna; Johnson, Rob; Aldred, Rachel; Murugesan, Manoradhan; Brage, Soren; Bhalla, Kavi; Woodcock, James; Goel, Rahul [0000-0002-4189-021X]; Garcia, Leandro MT [0000-0001-5947-2617]; Murugesan, Manoradhan [0000-0002-8625-9237]
    BACKGROUND: Street imagery is a promising and growing big data source providing current and historical images in more than 100 countries. Studies have reported using this data to audit road infrastructure and other built environment features. Here we explore a novel application, using Google Street View (GSV) to predict travel patterns at the city level. METHODS: We sampled 34 cities in Great Britain. In each city, we accessed 2000 GSV images from 1000 random locations. We selected archived images from time periods overlapping with the 2011 Census and the 2011-2013 Active People Survey (APS). We manually annotated the images into seven categories of road users. We developed regression models with the counts of images of road users as predictors. The outcomes included Census-reported commute shares of four modes (combined walking plus public transport, cycling, motorcycle, and car), as well as APS-reported past-month participation in walking and cycling. RESULTS: We found high correlations between GSV counts of cyclists ('GSV-cyclists') and cycle commute mode share (r = 0.92)/past-month cycling (r = 0.90). Likewise, GSV-pedestrians was moderately correlated with past-month walking for transport (r = 0.46), GSV-motorcycles was moderately correlated with commute share of motorcycles (r = 0.44), and GSV-buses was highly correlated with commute share of walking plus public transport (r = 0.81). GSV-car was not correlated with car commute mode share (r = -0.12). However, in multivariable regression models, all outcomes were predicted well, except past-month walking. The prediction performance was measured using cross-validation analyses. GSV-buses and GSV-cyclists are the strongest predictors for most outcomes. CONCLUSIONS: GSV images are a promising new big data source to predict urban mobility patterns. Predictive power was the greatest for those modes that varied the most (cycle and bus). With its ability to identify mode of travel and capture street activity often excluded in routinely carried out surveys, GSV has the potential to be complementary to new and traditional data. With half the world's population covered by street imagery, and with up to 10 years historical data available in GSV, further testing across multiple settings is warranted both for cross-sectional and longitudinal assessments.
  • ItemPublished versionOpen Access
    Diet quality and depressive symptoms in adolescence: no cross-sectional or prospective associations following adjustment for covariates.
    (Cambridge University Press (CUP), 2018-09) Winpenny, Eleanor M; van Harmelen, Anne-Laura; White, Martin; van Sluijs, Esther Mf; Goodyer, Ian M; Winpenny, Eleanor [0000-0003-1933-0168]; van Harmelen, Anne-Laura [0000-0003-1108-2921]; White, Martin [0000-0002-1861-6757]; Van Sluijs, Esther [0000-0001-9141-9082]; Goodyer, Ian [0000-0001-9183-0373]
    OBJECTIVE: Adolescence is a critical period for development of depression and understanding of behavioural risk factors is needed to support appropriate preventive strategies. We examined associations between adolescent diet quality and depressive symptoms, cross-sectionally and prospectively, in a large community cohort, adjusting for behavioural and psychosocial covariates. DESIGN: Prospective community-based cohort study (ROOTS). SETTING: Secondary schools in Cambridgeshire and Suffolk, UK. SUBJECTS: Study participants (n 603) who completed 4 d diet diaries at age 14 years and reported depressive symptoms (Moods and Feelings Questionnaire (MFQ)) at 14 and 17 years of age. RESULTS: Diet data were processed to derive a Mediterranean diet score (MDS) and daily servings of fruit and vegetables, and fish. At age 14 years, a negative association between fruit and vegetable intake and MFQ score was seen in the unadjusted cross-sectional regression model (β=-0·40; 95 % CI -0·71,-0·10), but adjustment for behavioural covariates, including smoking and alcohol consumption, attenuated this association. Fish intake and MDS were not cross-sectionally associated with MFQ score. No prospective associations were found between MDS, fruit and vegetable intake or fish intake and later MFQ score. CONCLUSIONS: Diet quality was not associated with depressive symptoms in mid-adolescence. Previously reported associations in this age range may be due to confounding. Further longitudinal studies are needed that investigate associations between adolescent diet and depression across different time frames and populations, ensuring appropriate adjustment for covariates.